In case you didn’t know, The Martian is based on Andy Weir‘s book of the same name, and as is the case with any adaptation of a book, there are some differences between the source material and the film. If you haven’t read the book already, or if you just don’t have an interest now that you’ve seen the movie, a new edition of What’s the Difference? runs through all the major differences between the book and film. Watch below.

Here are The Martian differences between the book and movie from CineFix:

There actually don’t seem to be any drastic differences between the movie and the book. A couple of characters seem to have been changed significantly, but that’s not anything surprising. Plus, the scene showing how Mark Watney (Matt Damon) came to be left behind on Mars happens in the beginning of the movie as opposed being a flashback in the middle of the book.

Aside from that smart move to open the movie with a bang, Drew Goddard seems to have quite loyally adapted the book’s story, tone and more. It helps that the book itself is already thoroughly entertaining, and Goddard was able to translate so much exposition and science into the movie without becoming a drag on the film’s pace or entertainment value.